alias - defines an alias for the specified command at - runs a specified script or command at a set later time. atq - shows jobs in the at utility queue. atrm - deletes the specified job from the at utility queue.
awk - pattern scanning and processing language
bash - uses the Bourne Again Shell command language to interpret commands from standard input or a file, or to launch a subshell.
bc - Performs calculations via its programming language.
bind - binds a keyboard sequence to a readline function or macro.
break - exits from a for , while , select , or until loop.
builtin - executes the specified shell built‐in command.
bzip2 - compresses using the Burrows–Wheeler block sorting text compression algorithm and Huffman coding.
caller - returns the context of any active subroutine call.
case - selectively executes commands based on pattern.
cd - changes the current directory to the specified directory. cat - lists the contents of the specified file. change - changes the password expiration date for the specified system user account.
chfn - changes the specified user account's current information. chgrp - changes the default group of the specified file or directory. chmod - changes system security permissions for the specified file or directory
chown - changes the default owner of the specified file or directory. chpasswd - reads a file of login name and password pairs and updates the passwords. chsh - changes the specified user account's default shell.
clear - clears text from a terminal emulator or virtual console. terminal.
command - executes the specified command without the normal shell lookup.
compgen - generates possible completion matches for the specified word.
complete - displays how the specified words would be completed.
compopt - changes options for how the specified words would be completed. compress - original Unix file compression utility.